1. Field of the Invention
The present invention relates to a vehicle rear-view mirror equipped with a display device that issues a warning to the driver, configured so that: when a warning is indicated, it is easy to see from the driver and is hard to see from following vehicles and vehicles on the adjacent lanes; and when no warning is indicated, no discontinuities occur in the image of the rear view and the warning symbols are unnoticeable.
2. Description of the Related Art
U.S. Pat. Nos. 5,313,335 and 6,099,154 each disclose a vehicle rear-view mirror equipped with a display device that emits warning light to the driver. U.S. Pat. No. 5,313,335 discloses a mirror having an indicator formed at a part of a surface of a mirror element, the indicator not constituting a part of the mirror surface, the mirror being configured so that when another vehicle is approaching, the indicator lights up to inform the driver of the vehicle's approach. U.S. Pat. No. 6,099,154 discloses a mirror having a mirror element formed of a semi-transmissive reflecting mirror, the mirror being configured so that indication masks with particular warning symbols drawn as transmissive patterns are arranged on the back surface of the mirror element, light sources are arranged behind the indication masks, and when a warning is necessary, a light source lights up to emit light for indicating a warning symbol through the semi-transmissive reflecting mirror, thereby informing the driver of the warning.
The mirror disclosed in U.S. Pat. No. 5,313,335 has a problem in that when no warnings are indicated (i.e., when the lights are put off), the rear-area image reflected in the mirror surface has discontinuities because the indicator does not constitute a part of the mirror surface, resulting in a poor design, and also in a narrow mirror surface area, causing a narrow range of vision. In the mirror disclosed in U.S. Pat. No. 6,099,154, the indication can easily be seen from any direction, which is obtrusive and accordingly provides a feeling of discomfort to following vehicles and vehicles on the adjacent lanes. Also, when no warnings are indicated, the warning symbols can easily be seen through the semi-transmissive reflecting mirror, which is obtrusive to the driver. In particular, the indication symbols are highly noticeable when light sources which are not of dark colors during the lights being put off are used or when a light diffusion plate of a white color is arranged between the light sources and the indication masks.
The present invention has been made in view of the aforementioned points, and aims to provide a vehicle rear-view mirror configured so that: when a warning is indicated, it is easy to see from the driver and is hard to see from following vehicles and vehicles on the adjacent lanes; and when no warning is indicated, no discontinuities occur in the image of the rear view and the warning symbols are unnoticeable.